<!DOCTYPE html>
<html>
<head>
<style>
body {
    margin: 0;
}

.testcase {
    position: absolute;
}

.testcase div {
    background-color: green;
}
</style>
</head>
<body>
This test passes if no red is showing.

<div style="position: relative; background-color: transparent;">

<div class="testcase" style="top:0; left: 0">
    <div style="width: 100px; height: 50px"></div>
    <div style="width: 100px; overflow-x: scroll"></div>
    <div style="width: 100px; height: 10px; position: relative; z-index: -1"></div>
</div>

<div class="testcase" style="height: 50px; -webkit-writing-mode: vertical-lr; top: 0; left: 150px">
    <div style="width: 100px"></div>
    <div style="overflow-y: scroll"></div>
    <div style="width: 10px; position: relative; z-index: -1"></div>
</div>

<div class="testcase" style="height: 50px; -webkit-writing-mode: vertical-lr; top: 0; left: 300px">
    <div style="width: 100px"></div>
    <div style="overflow-y: scroll"></div>
    <div style="width: 10px; position: relative; z-index: -1"></div>
</div>

<div class="testcase" style="top: 0; left: 450px">
    <div style="width: 100px; height: 50px"></div>
    <div style="width: 100px; overflow-x: scroll"></div>
    <div style="width: 100px; height: 10px; position: relative; z-index: -1"></div>
</div>

<div class="testcase" style="top: 100px; left: 0">
    <div style="width: 100px; height: 50px; "></div>
    <div style="width: 100px; overflow-x: scroll"></div>
    <div style="width: 100px; height: 10px; position: relative; z-index: -1"></div>
</div>

<div class="testcase" style="height: 50px; -webkit-writing-mode: vertical-lr; top: 100px; left: 150px">
    <div style="width: 90px; overflow-y: scroll"></div>
    <div style="width: 10px; position: relative; z-index: -1"></div>
</div>

<div class="testcase" style="top: 100px; left: 300px">
    <div style="width: 100px; height: 40px; overflow-x: scroll"></div>
    <div style="width: 100px; height: 10px; position: relative; z-index: -1"></div>
</div>

<div class="testcase" style="height: 50px; -webkit-writing-mode: vertical-lr; top: 100px; left: 450px">
    <div style="width: 100px"></div>
    <div style="overflow-y: scroll"></div>
    <div style="width: 10px; position: relative; z-index: -1"></div>
</div>


</body>
</html>
